The present invention is directed toward a device for tuning musical instruments and more particularly toward a device which employs a stroboscopic technique for tuning the instrument.
Stroboscopic tuning of musical instruments and particularly vibrating string instruments have been known for some time. Briefly, this is accomplished by shining a light on one of the strings desired to be tuned and strobing the light at a frequency equal to the desired frequency of the string. When the resonating frequency of the plucked string is equal to the frequency of the strobe light, the string appears to an observer to be stationary. When this occurs, the string has been tuned to the stroboscopic frequency. Such techniques and devices for accomplishing the same are described, for example, in U.S. Pat. No. 3,385,153 and U.S. Pat. No. 4,061,071.
There are times, however, when it is difficult or impossible to employ the basic stroboscopic tuning technique described above. For example, not everyone's eyesight is keen enough to see the vibrations of a vibrating string. And in some applications, such as in tuning an upright or spinet piano, the main part of the string, which moves the most during vibration, may be totally inaccessible.
Thus, there has been a need for a tuning device which has the exactness and simplicity of a stroboscopic tuner but which does not suffer from the drawbacks discussed above. Attempts have been made, heretofore, to accomplish this. For example, U.S. Pat. No. 3,861,266 and U.S. Pat. No. 4,014,242 describes systems using a simulated stroboscopic technique with a simulated rotating member. U.S. Pat Nos. 3,901,120 and 4,078,469 simulate a member in repeated unidirectional linear motion. However, none of these systems are believed to be satisfactory since they do not truly simulate the vibrations of a vibrating string. Since the string being tuned is vibrating, a device which simulates the vibrating action of the string is easier to visualize and relate to and, accordingly, would be easier to utilize by one tuning the instrument.